The invention relates to a device for sterilizing water flowing through a sanitary appliance, having
a) a housing, which comprises an inlet and an outlet for the water;
b) a UV lamp, which is disposed inside the housing and the radiation of which is directed towards the water flowing through;
c) a connection backplate, which is connectable to an external power source and has a location opening, into which a cap region of the UV lamp is insertable, wherein location opening and cap region have contacts which lie against one another in the operating position of the UV lamp.
In recent years the dangers arising in the field of sanitation from water contaminated with micro-organisms, in particular bacteria, amoebae or other monocellular organisms, have become ever clearer. Increased importance is therefore being attached to water sterilization. In said connection, there have been reports of experiments to sterilize flowing water through exposure to UV light, which is of a wavelength suitable for killing micro-organisms carried along in the water. To extend the retention time of said micro-organisms in the region of the UV lamp, an additional filtering apparatus may be used. The devices of the type described initially, which are known from said experiments, therefore comprised for connection of the UV lamp a connection backplate, the contacts of which had a direct or indirectly conductive connection to the external power source. Thus, when the housing of the device had to be opened to exchange the UV lamp, there was a risk of the contacts being live if the external power source had not been disconnected or isolated. For said reason and because of the deep-seated reluctance of plumbers to have anything to do with electrical appliances, the experimental built-on accessories of the initially described devices were unsuitable for practical use.
The object of the present invention is to refine a device of the type described initially in such a way that reliably rules out contact with live parts during operation and during repair or maintenance of the device and therefore dispels the misgivings about handling said devices felt by persons unused to dealing with electricity.
Said object is achieved according to the invention in that
d) the connection backplate is subdivided into two detachable, intermateable parts, of which the one is fastened to the housing and the other has the location opening;
e) the two parts of the connection backplate each contain a coil, which coils are adjacent to one another in the intermated state of the backplate, wherein the coil in the part fastened to the housing is connectable to the external power source and the coil in the other part is connected directly or indirectly to the contacts of the location opening of said part,
wherein
f) the location opening of the connection backplate is sealed against the cap region of the UV lamp.
According to the invention, there is therefore no conductive connectionxe2x80x94not even an indirect onexe2x80x94between the contacts in the location opening of the connection backplate and the external power source. Rather, the power transmission from one part of the connection backplate to the other is effected exclusively inductively in the manner of a transformer, wherein the primary and the secondary winding of said xe2x80x9ctransformerxe2x80x9d are situated on different parts of the connection backplate. Given said construction according to the invention, when the part of the connection backplate fastened to the housing is removed, there are no exposed contacts on it whatsoever. Even when the external power source is not isolated from said first part of the connection backplate, this poses no risks whatsoever. Separation of the two parts of the connection backplate immediately de-energizes the second part of the connection backplate, including the contacts disposed in its location opening. Whoever carries out maintenance work inside the device, e.g. exchanges the UV lamp, need not fear coming into contact with live parts. This gives the user a feeling of great confidence, which particularly in the case of water-carrying appliances is psychologically of an importance which should not be underestimated.
The connection of the two parts of the connection backplate may be effected, for example, in that the one of said two parts comprises a cylindrical neck which, in the intermated state of the connection backplate, projects into a complementary recess of the other part. In said manner, the two parts are provided with the xe2x80x9ctypicalxe2x80x9d configuration of a male and female connector part. The rotationally symmetric connection of the two parts of the connection backplate also enables a twisting of the housing part, e.g. a base, to which the one part of the connection backplate is fastened. Such twisting may be expedient when the housing part in question is, for example, detachably fastened by means of a screwed connection to the remaining housing.
The two coils in the two parts of the connection backplate, in the intermated state of the latter, are advantageously disposed coaxially with one another, one inside the other. Optimum efficiency of the inductive power transmission is thereby achieved.
It is further recommended that the two coils are enclosed, in particular encapsulated, in the respective parts of the connection backplate. In said manner the coils, which in any case do not require repair and therefore also need not be accessible, are reliably screened off from the water inside the device.
Operation of a UV lamp normally requires special voltages which are provided by separate control electronics. For said reason, a refinement of the invention is particularly preferred, in which the part of the connection backplate containing the location opening comprises control electronics, the input of which is connected to the coil in said part and the output of which is connected to the contacts of the location opening. Thus, the control electronics, which nowadays may be made very small, are integrated in the part of the connection backplate which is automatically de-energized when the housing is opened.
The control electronics, given the quality which is customary nowadays, are also so maintenance-free that they may be enclosed, in particular encapsulated, in the appropriate part of the location housing.
To intensify the effect of the UV lamp upon the micro-organisms situated in the water, there may be disposed in the housing a filtering apparatus, through which the water travelling between the inlet and the outlet of the housing has to pass and which is exposable to the light of the UV lamp. Said filtering apparatus, as the water flows through, retains the micro-organisms so that they are situated for a longer period in the, for them, lethal light of the UV lamp.
Finally, a refinement of the invention is preferred, in which a resilient pad is disposed between the end of the UV lamp remote from the connection backplate and the region of the housing adjacent thereto. Said resilient pad gently presses, on the one hand, the UV lamp with its cap region into the location opening of the connection backplate and, on the other hand, the part of the connection backplate having the location opening against the other part fastened to the housing.